Lighting ON/OFF and headlight dimmer switch confusion

[Arek]

Concerning a GS450 from 84-ish

I’m redoing the entire harness as it is a corroded mess. All in all it’s pretty straight forward, and actually an enjoyable learning process. I’m also changing out the handlebar controls which are coming from other models.

But! I have hit a wall with the Lighting ON/OFF and headlight dimmer switches. What makes is more confusing is that different wire diagrams show different things. Some don’t even show the lighting switch?

Currently (old to be switched out) what I have on my right handlebar controls is a lighting switch which has three positions:

• OFF
• what looks to be PARK (S)
• ON

The left one has a LOW / HI dimmer switch integrated into the LEFT / RIGHT indicator control.

So far so good!

The issue:
My understanding is that the right control turns the lights ON / OFF, and the left once decides whether to use LOW or HIGH. And please correctly if I’m wrong, but that requires +current to be sent from the right switch to the left handlebar control, which then switches between LOW (white wire) / HIGH (yellow wire) into the headlight. That connection however, seems to be missing on most wire diagrams I have found. The best I can find is the one I’m attaching here, where there is a thin line between the two switches.

The Questions:
1. What is this thin line between the two switches, is that a wire, which color?

2. What is the middle position on the lighting switch (marked S on mine). It’s not showing on any diagrams I have seen.

Screenshot 2020-03-13 at 10.43.34.jpg

P.S. I’m also eliminating the stator loop.

[posplayr]

Concerning a GS450 from 84-ish

I’m redoing the entire harness as it is a corroded mess. All in all it’s pretty straight forward, and actually an enjoyable learning process. I’m also changing out the handlebar controls which are coming from other models.

But! I have hit a wall with the Lighting ON/OFF and headlight dimmer switches. What makes is more confusing is that different wire diagrams show different things. Some don’t even show the lighting switch?

Currently (old to be switched out) what I have on my right handlebar controls is a lighting switch which has three positions:

• OFF
• what looks to be PARK (S)
• ON

The left one has a LOW / HI dimmer switch integrated into the LEFT / RIGHT indicator control.

So far so good!

The issue:
My understanding is that the right control turns the lights ON / OFF, and the left once decides whether to use LOW or HIGH. And please correctly if I’m wrong, but that requires +current to be sent from the right switch to the left handlebar control, which then switches between LOW (white wire) / HIGH (yellow wire) into the headlight. That connection however, seems to be missing on most wire diagrams I have found. The best I can find is the one I’m attaching here, where there is a thin line between the two switches.

The Questions:
1. What is this thin line between the two switches, is that a wire, which color?

2. What is the middle position on the lighting switch (marked S on mine). It’s not showing on any diagrams I have seen.

[ATTACH=CONFIG]60475[/ATTACH]

P.S. I’m also eliminating the stator loop.

As per the schematic the lighting switch has two position OFF and ON.

The diagram you point out is of the switch. It makes a connection where there is a short "wire" (line), in the indicated mode (either ON or OFF)

[Steve]

A few things going on here that are out of our (the US market) normal.
1. None of our bikes had a light switch on the right side.
2. Our bikes that did have a switch (up through '79, maybe a few through '80) had the switch on the LEFT side.
3. The combination up/down and left/right switch was rather common.
4. If you still have a stock Regulator/Rectifier (R/R), keep the 'stator loop'. If you have upgraded to a series-type R/R, you can eliminate the loop.

The thin line between the two switches appears on the diagram for my '80 850. It is actually a yellow/white wire. It starts at a connector where the stator loop happens. There is an orange/red wire that comes from the fuse, then loops back to a gray wire that feeds the instrument cluster. Along with that loop is the yellow/white wire that goes to the headlight selector switch.

If you do actually have a stator 'loop', you should not have a functioning headlight switch. However, things were a bit different in the European market. When we got the federal mandate to have the headlights ON all the time, the rest of the world was still allowed to choose. Rather than change the entire wiring harness, Suzuki chose to only change the sub-harness that went to the left hand grip switches. The headlight switch actually controlled two circuits at the same time. One was for the power to the headlight, the other interrupted one leg of the stator, which reduced the overall stator output and prevented the R/R from working so hard.

I believe that your right-side switch might be from a Honda or Kawasaki.

.

[Arek]

A few things going on here that are out of our (the US market) normal.
1. None of our bikes had a light switch on the right side.
2. Our bikes that did have a switch (up through '79, maybe a few through '80) had the switch on the LEFT side.
3. The combination up/down and left/right switch was rather common.
4. If you still have a stock Regulator/Rectifier (R/R), keep the 'stator loop'. If you have upgraded to a series-type R/R, you can eliminate the loop.

The thin line between the two switches appears on the diagram for my '80 850. It is actually a yellow/white wire. It starts at a connector where the stator loop happens. There is an orange/red wire that comes from the fuse, then loops back to a gray wire that feeds the instrument cluster. Along with that loop is the yellow/white wire that goes to the headlight selector switch.

If you do actually have a stator 'loop', you should not have a functioning headlight switch. However, things were a bit different in the European market. When we got the federal mandate to have the headlights ON all the time, the rest of the world was still allowed to choose. Rather than change the entire wiring harness, Suzuki chose to only change the sub-harness that went to the left hand grip switches. The headlight switch actually controlled two circuits at the same time. One was for the power to the headlight, the other interrupted one leg of the stator, which reduced the overall stator output and prevented the R/R from working so hard.

I believe that your right-side switch might be from a Honda or Kawasaki.

.

Thanks Steve,

Yes, this must be a European model where we are also driving with the lights on at all times, so I don't really need the switch.
So in reality I could just feed the dimmer switch directly from the orange wire, or is there another way of doing it?

I do have the stator loop in the old harness, so I guess the lighting switch never worked anyways?

I have a new R/R so should be OK to eliminate the stator loop as I understand it.


Here's a picture of the right and left handlebar controls.
Screenshot 2020-03-13 at 12.51.44.jpg

[Grimly]

My Euro 80 GS has the RH main on/off lighting switch. LH is purely for up/down. Still got the factory switch on the RH.
Otoh, my 79 has both main lighting controls on the LH, which made for exciting times when you went to change main to dip (or maybe vice versa) and switched the lights off entirely when a gloved thumb accidentally operated the adjacent slider switch. One of the crappiest designed switches ever.
Needless to say, when that goes back on the road the switchgear will be getting upgraded.

[Arek]

Otoh, my 79 has both main lighting controls on the LH, which made for exciting times when you went to change main to dip (or maybe vice versa) and switched the lights off entirely when a gloved thumb accidentally operated the adjacent slider switch.

Yiikes! Not the best UX design indeed.

[Gorminrider]

Haynes manual for GS450s and GSX400s has several diagrams. For the 84 GSX400,(UK) there's a passing switch beside the horn...You'd best be sure you have the right diagram...and the right handlebar switches-as steve said, it's not unheard of to adapt switches from other bikes either.

[Gorminrider]

hmm. i take it back...from an 81 GSX400L, I see a RIGHT HAND lighting switch...interesting! If you goto BassCliffs site, download the "GSX400 Service manual" (5.2 mb) It's really an addendum to the 250-300 manual. It's not a 450 (I only find these from Belgium and a few other continentals) but it might be the clue you need.
BikeCliff's Website
Screen-2020-03-13_18-41-43.jpg

[Arek]

hmm. i take it back...from an 81 GSX400L, I see a RIGHT HAND lighting switch...interesting! If you goto BassCliffs site, download the "GSX400 Service manual" (5.2 mb) It's really an addendum to the 250-300 manual. It's not a 450 (I only find these from Belgium and a few other continentals) but it might be the clue you need.
BikeCliff's Website

Yes, I do have a Haynes (and Clymer's for that matter), but was not aware that the GSX400 model had the same wiring as the GS450. After looking at it from a high level perspective, they look the same in terms of colouring etc. - except for the lighting switch of course.

[Gorminrider]

But the manual on bike-cliff's is different again. It is the Suzuki manual, not Haynes or Clymer. So I'd say get it and have a look.

yes the GS 450s and GSX400s are very similar except in the engine valves...

[steveb922]

I have the same two switches on my 1980 550. I don't know if it will help, but, given that Suzuki often used the same colour wiring for the same purpose, you may find a 550 wiring diagram more easily available?

[Gorminrider]

^^^ Good idea! I wouldn't be suprised if they match... clarity of the diagrams varies a lot in the "scanned" manuals too so look for the best one.

[Arek]

Hi All,

Here's an update.

After doing a lot of searching in different schematics, I figured it out. In Europe we have the lighting switch on the right hand, which sends + to the left hand dimmer switch. From here there are two options into the head lamp, HI or LO. Nothing hocus pocus about that!

Another thing I learned: you can pretty much do your wiring as you like on older / more simple bikes (well with some rules that don't allow to be bent), and since I'm redoing the entire harness, then I decided to do it the way I want it.

Here's an image of the finished harmes (with no heat shrink yet). Almost all wiring done in black as I did not bother to find 34 different colours at 6 different vendors, but all ends have these cenvron-shaped plastic clips on.

Screenshot 2020-03-21 at 15.42.17.jpg

[Gorminrider]

Yes, it'd be a real pain getting all the same colours..so what's a "cenvron-shaped plastic clip" ? Can't see in the little picture. Is it a methoed of "coding" the wires? Because of course you need something if all your wires are black and it might be a handy device for others.

[Arek]

Yes, it'd be a real pain getting all the same colours..so what's a "cenvron-shaped plastic clip" ? Can't see in the little picture. Is it a methoed of "coding" the wires? Because of course you need something if all your wires are black and it might be a handy device for others.

Basically they are these:
Screenshot 2020-03-22 at 20.18.29.jpg



I then have a key showing which number translates into which color. E.g Orange = 1, Black = 2 etc.